JP3190597B2 - Charge / discharge control circuit and rechargeable power supply - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charge / discharge control circuit capable of controlling charging / discharging of a secondary battery by turning on / off a switch circuit, and a rechargeable power supply using the circuit.

[0002]

2. Description of the Related Art As a conventional rechargeable power supply comprising a secondary battery, a power supply as shown in a circuit block diagram of FIG. 2 has been known. For example, such a structure is disclosed in Japanese Patent Application Laid-Open No. 4-75430, "Rechargeable power supply device".
That is, the secondary battery 101 is connected to the external terminal −V0 105 or + V0 104 via the switch circuit 103. Further, the charge / discharge control circuit 1 is connected in parallel with the secondary battery 101.
02 is connected. The charge / discharge control circuit 102 has a function of detecting the voltage and current of the secondary battery 101. The secondary battery 101 is in an overcharged state higher than a predetermined voltage value, an overdischarged state lower than a predetermined voltage value, or a current larger than a predetermined current value flows through the switch circuit 103 to reach a voltage at which the external terminal + V0 104 is present. In any of the overcurrent states described above, the charge / discharge prohibition signal 107 is output from the charge / discharge control circuit 102 so that the switch circuit 103 is turned off to stop the charge current or the discharge current.
Hereinafter, states in which the secondary battery 101 is in an overcharged state, an overdischarged state, or an overcurrent state and charging or discharging is stopped are referred to as an overcharge protection state, an overdischarge protection state, and an overcurrent protection state, respectively.

As another example of a conventional rechargeable power supply comprising a secondary battery, a power supply as shown in a circuit block diagram of FIG. 3 is also known. In this circuit, the switch circuit 103 shown in FIG. 2 is connected in series to the negative electrode side of the secondary battery, and the operation is the same as that of FIG. In general, the switch circuit 103 includes two FETs (Field
Effect Transistor is used.
As another conventional example using this switch circuit, a power supply device as shown in a circuit block diagram of FIG. 4 is also known. In FIG. 4, the switch circuit 103 has two FETs.
In an overdischarge state or an overcurrent state, F
The ET-A 112 is turned off to stop the discharge current, and in an overcharge state, the FET-B 113 is turned off to stop the charging current. Therefore, the signal for controlling the switch circuit is divided into two signals, a discharge inhibition signal 107A and a charge inhibition signal 107B.

As a conventional example having a more practical function, a power supply device as shown in a circuit block diagram of FIG. 5 is also known. In FIG. 5, the overcharge detection circuit 120
, Overdischarge detection circuit 121, overcurrent detection circuit 122, power down circuit 123, logic circuit 124, and delay circuit 1
29 together form a charge / discharge control circuit 102. In FIG. 5, the charger 108 is connected to the external terminal + V0 104
When the state in which the rechargeable battery 101 is higher than or equal to the upper limit value of the charging voltage continues for a predetermined time or more, the overcharge detection signal
Is output to the logic circuit 124. When the load 109 is connected between the external terminals + V0 104 and −V0 105 and the state in which the secondary battery 101 has fallen below the lower limit of the discharge voltage continues for a predetermined time or more, the overdischarge detection circuit 121 overdischarges. The detection signal 131 is output to the logic circuit 124. When the state where the discharge current flowing through the switch circuit 103 exceeds the upper limit value and the potential of the external terminal -V0 105 exceeds the predetermined value due to the ON resistance of the switch circuit 103 continues for the predetermined time or more, the overcurrent detection circuit From 122, an overcurrent detection signal 132 is output to the logic circuit 124. When the overcharge detection signal 130 is input, the logic circuit 124 can output the charging inhibition signal 107B to the FET-B113 to stop the charging current, and receive the overdischarge detection signal 131 or the overcurrent detection signal 132. Then, the discharge inhibition signal 107A is output to the FET-A112 to stop the discharge current.

The over-discharge detection signal 131 is output from the delay circuit 1
The signal is also output to the power-down circuit 123 through 29.
Then, the power-down circuit 123 outputs the power-down signal 133 to each circuit, and can stop the operation of each circuit so that the charge / discharge control circuit 102 does not consume power any more. Hereinafter, a state in which the operation of the charge / discharge control circuit 102 is stopped is referred to as a power down state. Charge / discharge control circuit 1
In the case of 02, once it enters the power down state, the operation is not restarted until charging is newly started.

The delay circuit 129 can output the overdischarge detection signal 131 to the power down circuit 123 only when the overdischarge detection signal 131 is continuously output for a predetermined time or more. The delay circuit 129 is effective when the voltage of the secondary battery 101 decreases due to an excessive discharge current and an overcurrent state and an overdischarge state occur simultaneously. That is, in the power supply device shown in FIG. 5, for a certain period of time after the occurrence of the overcurrent state, the overdischarge detection signal is stopped by the delay circuit 129 even if the overdischarge state occurs, and the power-down state is prohibited. Discharge circuit 10
Operation 2 is continued. The discharge prohibition signal 1
The time until the discharge current is stopped at 07A is predicted and set. Since the discharge current stops during the predetermined time and the discharge current stops, and the voltage of the secondary battery 101 is restored, the overdischarge state is set before the delay circuit 129 outputs the overdischarge detection signal. The circuit configuration is canceled and the voltage monitoring of the secondary battery 101 is restarted without entering the power down state. Even after entering the overcurrent protection state after the fixed time, the power of the charge / discharge control circuit 102 itself is consumed, so that the voltage of the secondary battery 101 gradually decreases,
If an overdischarge state occurs, the power down state is entered and the operation of the charge / discharge circuit 102 can be stopped.

[0007]

However, the conventional power supply device configured as shown in FIG. 5 has a problem that a malfunction occurs if the delay time until the discharge current is stopped is incorrectly set. Was. In addition, in order to actually reduce the malfunction, there is a problem that a sufficiently long delay time must be set as compared with the case where the discharge current stops and the voltage of the secondary battery returns. Further, the delay circuit 129 is complicated and has a problem that the circuit becomes large because a resistor, a capacitor and the like are used. Further, in many cases, the delay circuit 129 is used in practice as a delay circuit in the overdischarge detection circuit 121, in which case it is necessary to set the delay time longer than the delay time in the overcurrent detection circuit 122. There is a problem that the setting of the delay time of the detection circuit 121 is restricted.

Accordingly, an object of the present invention is to solve such a conventional problem by discharging a current, causing a voltage drop in the battery, and generating an overcurrent state and an overdischarge state together. A charge / discharge control circuit capable of reliably continuing the control operation, and immediately stopping the discharge current in an overdischarge state in other cases and then stopping its own control operation,
This is realized by using a simple and small circuit.

[0009]

In order to solve the above problems, a charge / discharge control circuit and a rechargeable power supply according to the present invention prohibit an overdischarge detection operation when an overcurrent state occurs, and thereafter perform a discharge operation. The circuit is configured to detect an operation in which the current stops and the battery voltage recovers, and release the prohibited overdischarge detection operation.

In the charge / discharge control circuit and the rechargeable power supply configured as described above, no malfunction occurs when the overcurrent state and the overdischarge state occur simultaneously only by using a simple and small detection circuit. Not only can the secondary battery be controlled, but there is no need to set a long delay time to prevent malfunction, and a complicated and large delay circuit for that is no longer necessary. In addition, the delay time of the overdischarge detection circuit can be freely set without any limitation, so that a wider range of needs can be met.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit block diagram showing an embodiment of a charge / discharge control circuit and a rechargeable power supply device of the present invention. In FIG. 1, the charge / discharge control circuit 102 is formed by combining the overcharge detection circuit 120, the overdischarge detection circuit 121, the overcurrent detection circuit 122, the power down circuit 123, the logic circuit 124, and the logic circuit A125.

In FIG. 1, the charger 108 is connected to the external terminal + V
When the state where the rechargeable battery 101 is higher than or equal to the upper limit of the charging voltage continues for a predetermined time or more, the overcharge detection signal 120 is output from the overcharge detection circuit 120 to the logic circuit. 124. When the load 109 is connected between the external terminals + V0 104 and −V0 105 and the state in which the secondary battery 101 has fallen below the lower limit of the discharge voltage continues for a predetermined time or more, the overdischarge detection circuit 121 overdischarges. The detection signal 131 is the logic circuit 124
Is output to When the state where the discharge current flowing through the switch circuit 103 exceeds the upper limit value and the potential of the external terminal -V0 105 exceeds the predetermined value due to the ON resistance of the switch circuit 103 continues for the predetermined time or more, the overcurrent detection circuit 1
From 22, an overcurrent detection signal 132 is output to the logic circuit 124. The logic circuit 124 outputs the overcharge detection signal 13
If 0 is input, the charge inhibition signal 107B is output to the FET-B1.
13, the charging current can be stopped, and when the overdischarge detection signal 131 or the overcurrent detection signal 132 is input, the discharge current can be stopped by outputting the discharge inhibition signal 107A to the FET-A112. it can.

The overdischarge detection signal 131 is also output to the power down circuit 123. Then, the power-down circuit 123 outputs the power-down signal 133 to each circuit, and can stop the operation of each circuit so that the charge / discharge control circuit 102 does not consume power any more. Hereinafter, a state in which the operation of the charge / discharge control circuit 102 is stopped is referred to as a power down state. Once the charge / discharge control circuit 102 enters the power down state, it does not resume operation until a new charge is started.

The overcurrent detection circuit 122 outputs an overdischarge detection inhibition signal 135A immediately when the overcurrent state occurs. The overdischarge detection prohibition signal 135A is connected to the logic circuit A12.
Then, the logic circuit A 125 outputs the over-discharge detection inhibition signal 135 B to the over-discharge detection circuit 121. Then, the overdischarge detection circuit 121 stops outputting the overdischarge detection signal 131 regardless of the voltage value of the secondary battery 101. After an elapse of a predetermined time, the overcurrent detection signal 132 is output.
Is output, the logic circuit A125 to which the discharge prohibition signal 107A is input cannot output the overdischarge detection prohibition signal 135B. Then, the overdischarge detection circuit 121 restarts the overdischarge detection operation, and according to the voltage value of the secondary battery 101,
The over-discharge detection signal 131 can be output.

[0015] This is because the secondary battery 1
01 is effective when the voltage of 01 drops and the overcurrent state and the overdischarge state occur simultaneously. That is, in the rechargeable power supply device of the present invention, the overcurrent detection signal 1
32 is output, and then until the discharge prohibition signal 107A is output, the over-discharge detection signal 131 is not output even if the over-discharge state occurs. Operation can now be continued reliably. Further, since the discharge prohibition signal 107A is output and the discharge current is stopped, and the overdischarge detection is restarted when the voltage of the secondary battery 101 is restored, the secondary battery is thereafter discharged by the power consumption of the charge / discharge control circuit 102 itself. When the voltage of 101 gradually decreases and enters an overdischarge state, the power supply immediately enters a power-down state to stop the operation of the charge / discharge circuit 102, thereby preventing further power consumption. . Moreover, in prohibiting the power-down state as in the conventional example, it is not necessary to secure a long delay time with a margin, and the overdischarge detection delay time can be set freely without being limited by the overcurrent detection delay time. As a result, complicated and large delay circuits are no longer necessary.

FIG. 6 is a circuit diagram showing an embodiment of the logic circuit A125 of the present invention. In FIG. 6, the NAND circuit 601 is shown.
Are input to the inverter circuit 602 to form the logic circuit A125. The discharge inhibition signal 107A and the overdischarge detection inhibition signal 135A are input to the input of the NAND circuit 601.
Is entered. In this embodiment, the FET-A for controlling the discharge
Since the transistor 112 is constituted by an NMOS transistor, the discharge inhibition signal 107A becomes Lo level. Further, both the overdischarge detection inhibition signal 135A and the overdischarge detection inhibition signal 135B are H
i. In the logic circuit A125 of FIG. 6, Hi is output from the inverter circuit 602 only when both input signals are Hi, and Lo is output in the other cases. That is, in the logic circuit A125 of FIG.
When 5A is output and the discharge inhibition signal 107A is not output, the overdischarge detection inhibition signal 135B can be output. Thus, the logic circuit A125
Can be configured with a very simple and small circuit as compared with the conventional delay circuit 129. Therefore, the charge / discharge control circuit of the present invention can be manufactured small and inexpensively. Alternatively, the logic circuit A125 can have a configuration in which a detector circuit is provided, and can have a variety of circuit configurations regardless of the embodiment.

The power supply of the present invention has a discharge inhibition signal 107A.
Is detected and the overdischarge detection prohibition signal 135B is released, so that strictly, the stop of the discharge current is not detected. However, even if the over-discharge detection prohibition signal 135B is released instantaneously, the operation of the FET-A 112 to stop the discharge current is usually several μs, and the over-discharge detection circuit 121
Since the time during which the overdischarge detection signal 131 is output via the delay circuit of several tens to several hundreds of μs is sufficiently faster, the voltage of the secondary battery 101 is restored during that time, and there is no problem. Therefore, the same effect as detecting the stop of the discharge current can be obtained.

FIG. 11 is a timing chart of signals in the charge / discharge control circuit and the rechargeable power supply according to the present invention from the occurrence of an overcurrent state to the start of an overcurrent protection state. In FIG. 11, when an overcurrent state occurs, the potential of the external terminal -V0 105 increases, and the overcurrent detection circuit 12
2 detects point a and outputs Hi, which is an overcurrent detection signal 132 after a predetermined delay time. Next, the logic circuit 124
Detects the point b and outputs Lo which is the discharge prohibition signal 107A. Next, the FET-A 112 detects the point c and stops the discharge current. At this time, in the embodiment of FIG.
12, the logic circuit A125 detects the point e and can release the overdischarge detection inhibition signal 135B.
Here, as shown by points c and e in FIG. 11, the operating point e of the input stage to which the discharge inhibition signal 107A is input is the operating point c of the input stage of the FET-A112.
Designed to be lower. In this design, the timing at which the discharge current is stopped earlier than the release of the overdischarge detection inhibition signal 135B can be established only by adjusting the operating point without increasing other circuits, so that the charge / discharge control circuit of the present invention can be manufactured at low cost. Can be provided and very desirable.

When the discharge current stops, the overdischarge detection inhibit signal 1
A delay circuit may be provided to establish a timing earlier than the release of 35B. In this case, since the delay circuit requires only a short delay time, unlike the delay circuit 129 of the conventional example, the delay circuit can be downsized. Next, another embodiment of the charge / discharge control circuit and the rechargeable power supply device of the present invention will be described.

FIG. 7 is a circuit block diagram showing another embodiment of the charge / discharge control circuit and the rechargeable power supply of the present invention.
7 is different from FIG. 1 in that the logic circuit A125 is changed to a logic circuit B126, and the voltage value of the external terminal -V0 105 is input to the logic circuit B126. Other circuit operations are the same as those in FIG. FIG. 8 is a timing chart of each signal in the charge / discharge control circuit and the rechargeable power supply device of the present invention from the occurrence of an overcurrent state to entering the overcurrent protection state. In FIG. 8, when an overcurrent state occurs, the potential of the external terminal -V0 105 rises, the overcurrent detection circuit 122 detects the point a, and outputs Hi as the overcurrent detection signal 132 after a predetermined delay time. . Next, the logic circuit 124 detects the point b and outputs the discharge inhibition signal 107A.
Is output. Next, the FET-A 112 detects the point c and stops the discharge current. Then, as the discharge current stops, the potential of the external terminal -V0 105 is pulled up to the connected load and the external terminal + V0 10
It rises to the potential of 4. At this time, in the embodiment of FIG. 7, the logic circuit B126 can detect the point d of FIG. 8, and thereby the overdischarge detection inhibition signal 135B can be released. The logic circuit B126, like the logic circuit A125, can be small, simple, and have various configurations.

In the case of the embodiment shown in FIG. 7, since the overdischarge detection inhibition signal 135B is released by detecting the potential of the external terminal -V0 105 which rises due to the stop of the discharge current, the stop of the discharge current is monitored. Will be. Thereby, the same effect as that of the embodiment of FIG. 1 can be obtained. Next, another embodiment of the charge / discharge control circuit and the rechargeable power supply device of the present invention will be described.

FIG. 9 is a circuit block diagram showing another embodiment of the charge / discharge control circuit and the rechargeable power supply of the present invention.
FIG. 9 is different from FIG. 1 in that the secondary battery 101 and the FET-A11
2, a discharge current detection circuit 128 is connected in series. When the discharge current stops, the discharge current detection circuit 128 outputs a discharge current stop signal 138. Discharge current stop signal 1
38 is input to the logic circuit C127. Other circuit operations are the same as those in FIG.

FIG. 10 is a circuit diagram showing an embodiment of the discharge current detection circuit 128 in the charge / discharge control circuit of the present invention. In FIG. 10, a SENS resistance circuit 1001, a detector circuit 1002, and a reference voltage circuit 1003 constitute a discharge current detection circuit 128. Discharge inhibition signal 107
When the FET-A 112 stops discharging due to A and the discharge current decreases, the current flowing through the SENS resistance circuit 1001 decreases and the voltage input to the detector circuit 1002 decreases. The discharge current detection circuit 128 detects that the discharge current has stopped by comparing the voltage generated by the SENS resistance circuit 1001 with a reference voltage circuit 1003 that can output a predetermined voltage value.
8 can be output. When the discharge current stop signal 138 is input, the logic circuit C127 outputs the overdischarge detection inhibition signal 135B.
Can be canceled. As described above, the discharge current detection circuit 128 is not only simple and small, but also can have various circuit configurations. The logic circuit C127 also
As with the logic circuit A125, a small, simple, and diverse configuration can be employed.

In the case of the embodiment shown in FIG. 9, the voltage which is reduced by stopping the discharge current is detected, and the overdischarge detection inhibition signal 135 is detected.
Since B is released, the stop of the discharge current is monitored. Thereby, the same effect as that of the embodiment of FIG. 1 can be obtained. As described above, in the charge / discharge control circuit and the rechargeable power supply device of the present invention, the operation of prohibiting the overdischarge detection and stopping the discharge current immediately after the occurrence of the overcurrent state, or the phenomenon caused by the stop of the discharge current The essential point is that the circuit configuration is such that the overdischarge detection prohibition is canceled by detecting the overdischarge, and the present invention is not limited to the embodiment.

The charge / discharge control circuit and the rechargeable power supply according to the present invention adopt such a circuit configuration, so that when the overcurrent state and the overdischarge state occur simultaneously, the power down state is not entered, and the charge / discharge state is not reached. The operation of the control circuit can be reliably continued. In addition, since the discharge current stops after entering the overcurrent protection state and the overdischarge detection is restarted immediately after the voltage of the secondary battery is restored, the voltage of the secondary battery is thereafter reduced by the power consumption of the charge / discharge control circuit itself. When it gradually descends and enters the overdischarge state, it immediately enters the power down state, stops the operation of the charge / discharge control circuit, and can prevent further power consumption. As a result, wasteful power consumption of the secondary battery can be prevented, and the battery life can be extended. In addition, it is no longer necessary to secure a long delay time with a margin when prohibiting the power-down state as in the past, and the overdischarge detection delay time can be set freely without being limited by the overcurrent detection delay time. Became. In addition, a complicated and large delay circuit is not required, and instead a small and simple detection circuit and a logic circuit can be used, so that a small and inexpensive charge / discharge control circuit and a rechargeable power supply can be manufactured, and a battery pack and The cost of mobile devices and the like that use it could be reduced.

[0026]

According to the charge / discharge control circuit and the rechargeable power supply of the present invention, the operation for entering the power-down state or the operation for inhibiting the power-down state can be performed by merely changing the circuit as described above. It has the effect that it can be managed reliably. This has the effect of providing a charge / discharge control circuit that does not malfunction. Therefore, the charge / discharge management of the secondary battery can be performed accurately, and the cycle life of the secondary battery can be extended.

In addition, there is an effect that it is not necessary to secure a long delay time as in the prior art in order to guarantee the correct operation of the charge / discharge control circuit. Further, there is an effect that the overdischarge detection delay time can be freely set without being limited by the overcurrent detection delay time. In addition, a complicated and large delay circuit is not required, and a simple and small detection circuit may be added instead. Further, since the circuit area can be reduced, there is an effect that a small and inexpensive charge / discharge control circuit and a rechargeable power supply device can be provided. Accordingly, there is an effect that a secondary battery pack and a portable device using the secondary battery pack can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing an embodiment of a charge / discharge control circuit and a rechargeable power supply device of the present invention.

FIG. 2 is a circuit block diagram illustrating an example of a conventional rechargeable power supply device.

FIG. 3 is a circuit block diagram showing another example of a conventional rechargeable power supply device.

FIG. 4 is a circuit block diagram showing another example of a conventional rechargeable power supply device.

FIG. 5 is a circuit block diagram showing another example of a conventional charge / discharge circuit and a rechargeable power supply device.

FIG. 6 shows a logic circuit A in the charge / discharge control circuit of the present invention.
FIG. 125 is a circuit diagram showing an embodiment of the present invention.

FIG. 7 is a circuit block diagram showing another embodiment of the charge / discharge control circuit and the rechargeable power supply device of the present invention.

FIG. 8 is a timing chart of each signal in the charge / discharge control circuit and the rechargeable power supply of the present invention from the occurrence of an overcurrent state to the start of an overcurrent protection state.

FIG. 9 is a circuit block diagram showing another embodiment of the charge / discharge control circuit and the rechargeable power supply device of the present invention.

FIG. 10 is a circuit diagram showing an embodiment of a discharge current detection circuit 128 in the charge / discharge control circuit of the present invention.

FIG. 11 is a timing chart of each signal from the occurrence of an overcurrent state to the start of an overcurrent protection state in the charge / discharge control circuit and the rechargeable power supply device of the present invention.

[Explanation of symbols]

 101 Secondary Battery 102 Charge / Discharge Control Circuit 103 Switch Circuit 104 External Terminal + V0 105 External Terminal -V0 107 Charge / Discharge Inhibition Signal 107A Discharge Inhibition Signal 107B Charge Inhibition Signal 108 Charger 109 Load 112 FET-A 113 FET-B 120 Overcharge Detection circuit 121 Overdischarge detection circuit 122 Overcurrent detection circuit 123 Power down circuit 124 Logic circuit 125 Logic circuit A 126 Logic circuit B 127 Logic circuit C 128 Discharge current detection circuit 129 Delay circuit 130 Overcharge detection signal 131 Overdischarge detection signal 132 Overcurrent detection signal 133 Power down signal 135A Overdischarge detection inhibition signal 135B Overdischarge detection inhibition signal 137 Discharge current stop signal 601 NAND circuit 602 Inverter circuit 1001 SENS resistance circuit 1 02 detector circuit 1003 reference voltage circuit

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-104015 (JP, A) JP-A-6-105458 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02J 7/00-7/12 H02J 7/34-7/36 H02H 7/18

Claims (4)

(57) [Claims] 1. A switch connected in series to an external power supply terminal
Circuit of a rechargeable power supply having a circuit and a secondary battery.
Connected in parallel with the secondary battery to control the switching circuit.
In the discharge control circuit, at the time of an overcurrent in which an excessive current flows in the switch circuit, or
At the time of overdischarge in which the voltage of the secondary battery has dropped,
Turn off the switch circuit and connect the external power
And means having a function of stopping the discharge current to the terminal, after the in overdischarge stopping the discharge current, the charge
Means having a function of stopping the operation of the discharge control circuit itself
If, stops the operation of the charging and discharging control circuit itself when the overcurrent
Hand with the function of prohibiting the operation of means having the function of performing
And detecting an operation of stopping the discharge current at the time of the overcurrent.
The function of stopping the operation of the charge / discharge control circuit itself is restored.
A charging / discharging control circuit comprising: 2. A switch connected in series to an external power supply terminal
Circuit and secondary battery, and for controlling the switch circuit
And a charge / discharge control circuit connected in parallel to the secondary battery.
In the rechargeable power supply device, at least the charge / discharge control circuit operates when an excessive current flows through the switch circuit, or
During overdischarge when the voltage of the secondary battery has dropped, the switch
Switch off the external power supply terminal from the secondary battery.
Means having a function of stopping the discharge current to the battery; and
Means having a function of stopping the operation of the discharge control circuit itself
If, stops the operation of the charging and discharging control circuit itself when the overcurrent
Means having a function of prohibiting the function of performing the function of detecting the operation of stopping the discharge current when the overcurrent occurs.
Function to stop the operation of the charge / discharge control circuit itself
Means having the function of causing
Electric power supply . 3. A switch connected in series to an external power supply terminal.
In a rechargeable power supply having a circuit and a secondary battery ,
Connected to the secondary battery in parallel to control the switch circuit.
In the continuous charge / discharge control circuit, at the time of an overcurrent when an excessive current flows through the switch circuit or
During overdischarge when the voltage of the secondary battery has dropped, the switch
Switch off the external power supply terminal from the secondary battery.
Means having a function of stopping the discharge current to the battery; and
Means having a function of stopping the operation of the discharge control circuit itself
If, stops the operation of the charging and discharging control circuit itself when the overcurrent
Hand with the function of prohibiting the operation of means having the function of performing
And the current caused by stopping the discharge current during the overcurrent.
And stops the operation of the charge / discharge control circuit itself.
A means having a function of restoring the function . 4. A switch connected in series to an external power supply terminal
Circuit and secondary battery, and for controlling the switch circuit
And a charge / discharge control circuit connected in parallel to the secondary battery.
In the rechargeable power supply device, at least the charge / discharge control circuit operates when an excessive current flows through the switch circuit, or
During overdischarge when the voltage of the secondary battery has dropped, the switch
Switch off the external power supply terminal from the secondary battery.
Means having a function of stopping the discharge current to the battery; and
Means having a function of stopping the operation of the discharge control circuit itself
If, stops the operation of the charging and discharging control circuit itself when the overcurrent
Means having a function of prohibiting the function of performing the operation, and the discharge current stops when the overcurrent occurs.
Detect the phenomenon and stop the operation of the charge / discharge control circuit itself
Means having the function of restoring the function
Characteristic rechargeable power supply.